While hydrometallurgical and mineral processing approaches became substantially more competitive in the last decades, materials containing multiple elements can often be challenging to process with these methods, leading to high operating costs. As an example, many attempts were made to recycle smelter dust hydrometallurgically to recover minor elements, such as Cu, Pb, Sb, Bi, Ag, Au, Ge and In. Such processes generally resulted in complicated flow sheets (water balance, chloride limits, heat balance, water contamination, operating costs, etc.).
There is thus a need for at least providing an alternative or complementary technology to the existing solutions for treating such dust residues and/or other polymetallic raw materials.